Sudoku with sum clues

Killer Sudoku

The puzzle is made the moment you press. Nothing is recorded. Play full screen

Each outlined group has its sum in one corner. Add up, and the digits start to show.

Play one now How to play

Made by the same generator as the app: one answer, reachable by logic alone. Hints come in three steps.

What makes it fun

The sum comes before the answer
Every cell belongs to an outlined group with a fixed sum.
Addition joins the sudoku
Add the digits to check them as you fill the grid.
The same total can hold different digits
Which digits fit depends on the other groups too.

Try one on the board above

Rules

Each row, column and 3×3 box holds 1–9 exactly once.
The small number in a cage's corner is the sum of its cells.
No digit repeats inside a cage, even when the cage crosses boxes.

SOLVED WHENSolved when every cell holds the right digit.

Your first move

Start with the smallest cages. A two-cell cage adding to 3 or 17 has only one possible pair of digits.

When you get stuck

Hints come in three steps: where to look, why it works, then the answer. The first step only shows the place, so you can still find the rest yourself.

Controls

Long-press to enter: Long-press a cell, slide to a digit and let go. Let go outside the keypad to enter nothing.
Cell, then number key: Tap a cell, then press a number key.
Digit first: To place the same digit in many cells, pick its key once, then tap each cell.
Notes: Double-tap a cell or switch on Notes to write small candidates. Notes never count as mistakes.
Erase and Undo: Erase clears the selected cell. Each press of Undo goes back one move.